Among viruses, human immunodeficiency virus (hereafter, referred to as HIV), a kind of retrovirus, is known to cause acquired immunodeficiency syndrome (hereafter, referred to as AIDS). The therapeutic agent for AIDS is mainly selected from a group of reverse transcriptase inhibitors (e.g., AZT, 3TC, etc.) and protease inhibitors (e.g., Indinavir, etc.), but they are proved to be accompanied by the following problems: side effects such as nephropathy, the emergence of resistant viruses, and the like. Thus, the development of anti-HIV agents having the other mechanisms of action therefrom has been desired.
On the other hand, currently, a multiple combination therapy is reported to be efficient in treatment for AIDS because of the frequent emergence of the resistant mutant virus. Two kinds of reverse transcriptase inhibitors and protease inhibitors are clinically used as an anti-HIV agent; however agents having the same mechanism of action often exhibit cross-resistance or only an additional activity. Therefore, development of anti-HIV agents having the other mechanism of action is desired.
Under the circumstances above, an integrase inhibitor has been focused on as an anti-HIV agent having a novel mechanism of action (Ref: Patent Documents 1 and 2). As an anti-HIV agent having such a mechanism of action, known are carbamoyl-substituted hydroxypyrimidinone derivative (Ref: Patent Document 3) and carbamoyl-substituted hydroxypyrrolidione derivative (Ref: Patent Document 4). Further, a patent application concerning carbamoyl-substituted hydroxypyridone derivative has been filed (Ref: Patent Document 5, Example 8).
Further, other known carbamoylpyridone derivatives include 5-alkoxypyridine-3-carboxamide derivatives and γ-pyrone-3-carboxamide derivatives, which are a plant growth inhibitor or herbicide (Ref: Patent Documents 6-8).
Furthermore, other HIV integrase inhibitors include nitrogen-containing condensed cyclic compounds (Ref: Patent Document 9).
Moreover, other HIV integrase inhibitors are known, and in such compounds, the terminal of an amide side chain is aryl (Ref: Patent Documents 10 and 11).
In addition, the present applicant filed a patent application of an anti-influenza agent comprising a nitrogen-containing condensed cyclic compound as an active ingredient (Japanese Patent Application No.: 2009-142166).